Many watercraft have been previously proposed in which the means for propelling the craft comprise a foot pedal drive assembly. For example, so-called water bicycles have been disclosed in U.S. Pat. Nos. 858,093; 837,973 and 1,920,391 in which floats or pontoons are permanently connected to specially designed bicycle-type frames. However, this type of watercraft has the distinct disadvantage of only being usable in water since no wheels are provided for use on land. A second general type of watercraft has also been proposed in which bicycles having wheels are further provided with multiple pontoons which may be removed or retracted such as disclosed in U.S. Pat. Nos. 2,304,430 and 2,757,631. However, this type of watercraft has the disadvantage of being mechanically complex, awkward to carry on land, and/or difficult to connect and disconnect the bicycle and its drive chain from the propeller drive mechanism. A third type of watercraft has also been proposed such as disclosed in U.S. Pat. Nos. 587,074 and Dutch Pat. No. 13,687 in which a conventional bicycle is mounted on a one-piece boat hull. While this type of design has the advantage of being able to connect and disconnect the bicycle relatively easy for separate use of the bicycle on land, the large one-piece construction of the boat hull makes it very difficult to handle or carry on land, and it is impossible to carry it on the bicycle. In addition, the long one-piece hull construction with only a rear rudder for steering gives the boat a very large turning radius such that it cannot be turned around in a narrow stream or small pond.